1. Field of the Invention
The present invention relates to an alarm management system. More particularly, the invention relates to a system and method for managing alarms in an industrial facility. Even more particularly, the present invention relates to a system and method for managing a plurality of alarms in a nuclear power plant.
2. Description of Related Art
Day to day operations in most industrial facilities, including nuclear power generation plants, are typically uneventful. However, certain unscheduled events may occur that require the immediate attention of operational personnel. Thus, most process parameter monitoring systems are designed to include some type of warning system to alert operational personnel to an impending, or current, event requiring their attention. More specifically, these systems typically sound an audible alarm to alert operational personnel that a process parameter has exceeded a specified limit.
Some unscheduled events may result in numerous alarms being sounded. These alarms may come from different systems, require differing levels of attention, and require attention by different operational personnel. Thus, when multiple alarms sound simultaneously or in momentary succession, operational personnel must determine what system each alarm is associated with, the priority level of each alarm, and which operator is responsible for attending to each alarm. This may result in confusion, missed alarms, inattention to certain alarms, or a combination of all of these factors, especially if the alarms are spread out around the facility.
Designers have attempted to alleviate the above-mentioned factors to some extent in the nuclear power plant context. Specifically, modern nuclear power plants utilize a centralized control room design having computer-based workstations to allow convenient access to plant controls and functions from a single location. The workstations are divided into assigned operational responsibilities. For example, the reactor operator workstation encompasses controls and functions associated with reactor operations (e.g., primary plant systems including the nuclear reactor), and the turbine operator workstation encompasses controls and functions associated with secondary plant operations (e.g., steam plant systems). When one or more alarm situations occur, an alarm system outputs an audible tone to alert the control room operators. The system further causes the alarms to be depicted on workstation video display units as alarm lists, or highlighted on system mimic diagrams. The alarm lists may be filtered by certain categories such as by alarm priority or by the system in which the alarms occur.
However, even modem centralized control room designs exhibit certain deficiencies. Specifically, when an audible tone is generated upon occurrence of a new alarm, the operators must manually determine which operator has responsibility for the alarm. This is accomplished by manually scanning an alarm list to determine if the new alarm is associated with the reactor operator or the turbine operator. Or, the control room operators must examine the various system mimic diagrams on the video display units to make the determination. Both of these operations are time consuming and distracting.
Additionally, while the alarm lists may be filtered by certain categories, there is no coherent alarm status overview that allows an operator to conveniently observe the overall alarm-state of the plant and how the alarms are distributed.
An operator can readily determine individual alarms and groups of related alarms using the category filtering function, but it is difficult to ascertain the overall plant alarm-state and determine the distribution of the alarms.
Finally, present alarm systems provide no implementation that supports direct access to an operator""s desired view of one or more alarms from a high-level plant alarm status overview. For example, an operator may wish to observe a new alarm from different perspectives, such as from an alarm list or from within a system mimic diagram to observe the context of the alarm relative to associated plant components and systems. With present alarm systems, an operator must either manually search through a display menu to select the desired system mimic diagram or manually recall an appropriate alarm list.
Thus, there is a need for an alarm annunciation system that notifies operators immediately, upon the occurrence of one or more alarms, which operator has responsibility for each alarm. There is also a need for an alarm distribution indication system that presents a coherent view of the current plant alarm-state and the distribution of alarms by operator responsibility, priority, and system. There is additionally a need for a device for selectively displaying alarms that supports direct access to an operator""s desired view of one or more alarms from a high-level plant alarm status overview. Finally, there is a need for an entire alarm management system that incorporates each of these features.
In one aspect of the present invention, an alarm management system comprises receiving means, comparing and generating means, receiving and transmitting means, and sound generation means. The receiving means receives one or more process parameter signals representative of one or more process parameters. The comparing and generating means compares each of the received process parameter signals with an associated alarm setpoint and generates an alarm status signal on the basis of the comparison. The receiving and transmitting means receives the alarm status signal and transmits an annunciation command signal on the basis of the received alarm status signal. The sound generation means generates a sound on the basis of the annunciation command signal.
In another aspect of the present invention, an alarm annunciation system comprises receiving and transmitting means, tone generation means, and voice synthesization means. The receiving and transmitting means receives an alarm status signal and transmits an annunciation command signal on the basis of the received alarm status signal. The tone generation means generates a plurality of tones, each having a different frequency from another, on the basis of the annunciation command signal. The voice synthesization means synthesizes a human voice signal of a specified pitch on the basis of the annunciation command signal.
In still a further aspect of the present invention, an alarm distribution indication system comprises memory means, information extraction means, information categorization means, and display means. The memory means stores alarm information of a plurality of alarms. The information extraction means periodically extracts the alarm information from the memory means. The information categorization means categorizes the extracted alarm information into to a plurality of predetermined categories. The display means displays the alarm information, for each of the plurality of alarms, arranged into the plurality of predetermined categories.
In yet another aspect of the present invention, a device for selectively displaying a plurality of alarms, comprises a video display unit, an input selection device, information storage means, information categorization means, mimic display storage and generation means, and information transfer means. The information storage means stores alarm information for each of the plurality of alarms. The information categorization means periodically retrieves and categorizes the stored alarm information into a plurality of predetermined categories. The mimic display storage and generation means stores mimic display information for a plurality of process systems, and periodically retrieves the stored alarm information and generates the mimic display information for each of the plurality of process systems including the retrieved alarm information therein. The information transfer means receives a first command from the input selection device to select information and transfers the selected information to the video display unit for display thereon. The selected information includes one of the alarm information in one of the first plurality of predetermined categories, and the alarm information included in one of the plurality of process system mimic displays.
In yet still a further aspect of the present invention, a method of managing a plurality of alarms includes the steps of receiving, comparing, generating an alarm status signal, receiving the alarm status signal, transmitting an annunciation signal, and generating a sound. In the receiving step, one or more process parameter signals representative of one or more process parameters are received. In the comparing step, each of the received process parameter signals is compared with an associated alarm setpoint. In the alarm status signal generating step, an alarm status signal is generated on the basis of the comparison in the comparison step. The alarm status signal is received in the alarm status signal receiving step. An annunciation command signal is transmitted on the basis of the received alarm status signal, in the annunciation command signal transmission step. A sound is generated on the basis of the annunciation command signal, in the sound generation step.
The present invention provides distinct features and advantages over related alarm management systems and components. Specifically, an alarm annunciation system directs attention to the appropriate operational personnel whenever a new alarm is generated, or when an existing alarm condition returns to normal. Thus, operators are not required to manually determine which operator is responsible for the alarm.
An alarm distribution indication system provides a single display page on a video display unit from which operators can conveniently ascertain the overall alarm state and alarm distribution. Thus, operators do not have to mentally construct an overview of the overall alarm state and distribution by examining and filtering various alarm lists.
Additionally, a device for selectively displaying a plurality of alarms allows operators to conveniently and rapidly access one or more alarms based on a desired contextual view. Thus, operators do not have to manually search through a display menu to select a desired mimic display or manually recall the appropriate alarm list.
These and other features and advantages of the present invention will become more apparent to those skilled in the art when the following detailed description is read in conjunction with the accompanying drawings.